Luxembourg: illegal cannabis contaminated with mycotoxins

A Luxembourgish study, originating from the Health Protection and Legal Medicine Departments of the National Health Laboratory (LNS), and published in the journal Mycotoxin Research, studied the presence of dangerous mycotoxins in 142 samples of illegal cannabis seized by Luxembourg police.

Through chromatographic analyses, which separate the different substances present in a product, the study found that approximately one-third of the samples were contaminated with ochratoxin A, at concentrations up to 16mg/kg.

Ochratoxin is produced by different species of’Aspergillus and Penicillium, and mold which can impair the immune system's effectiveness or even be neurotoxic. Mycotoxins are also resistant to sterilization and heat. The mycotoxins most often develop during cultivation rather than during storage. These fungi are known to be mutagenic and carcinogenic because of their ability to break DNA strands and inhibit DNA repair mechanisms.

The maximum levels set by the European Commission in food are 15-20 mg/kg.

Among the samples, no significant difference was observed between those of resin and those of grass. Overall, concentrations remain low and do not suggest a problem for human health if cannabis consumption remains moderate.

Luxembourgish researchers write that «Recreational cannabis is being legalized in more and more countries, and methods for determining contaminants, and therefore mycotoxins, are starting to appear in the scientific literature. On the other hand, cannabis continues to be available on the illegal market without any quality control.

A previous Spanish study had determined that 75%, a type of hashish from Madrid, was contaminated with fecal bacteria, clearly rendering it unfit for human consumption.